Monoclonal antibodies selective against various human malignancies would be powerful diagnostic and possibly therapeutic tools. The ability to raise interspecies antibodies against the desired, but unknown, antigens depends upon the strategies employed. The purpose of this study is to concentrate on a few common human tumors and to use a variety of strategies with regard to preparation of the immunogen, mode of immunization, schedule of immunization and strains of laboratory animals to develop a panel of monoclonal antibodies against adenocarcinoma and epidermoid carcinoma of the lung, and by mass screening, to select those with the greatest potential for use in clinical practice. Human adenocarcinoma and epidermoid carcinoma of the lung lines have been obtained and are growing well in standard tissue culture. Antigens from antigen-antibody complexes of these tumors have also been developed and are currently frozen. Immunizations shall commence as soon as sufficient assay systems and the personnel to use them are in place.